The present invention provides a method of manufacturing a TFT substrate, in which method a data signal line is separated into upper and lower regions at a separating point that is not around above a scan signal line but in a region where an i-layer and an n+ layer formed on a gate insulating film are removed away in a flattened region of a gate insulating film. The seed film includes one or more noble metal layers, where each layer of the one or more noble metal layers is no greater than a monolayer. Data intended for a user utilizing a lower order modulation can be reliably detected, and if properly processed, used as pilots for a user that is trying to receive a higher order modulation. Furthermore, the pre-fetch data is stored in a passive preservation mode in the present cache device. The current source circuit has high output impedance utilizing gain-boosting techniques. The gate electrode, the source electrode and the drain electrode are connected electrically to a scan line, a data line and the pixel electrode respectively.